In general, the present invention relates to retractable aircraft landing gears and more particularly, to a landing gear of the type that includes an elongate shock strut having an upper end pivotally mounted to the aircraft frame about a retraction axis for pivotal displacement between a vertical, downwardly extending, landing and ground support position and a horizontal, retracted position nested within a landing gear well provided in a lower surface of the aircraft wing or fuselage.
In such landing gears, the shock strut is provided by telescopically disposed cylinder and piston members defining an internal pneumatic spring chamber. Air pressure within the chamber biases the strut toward a telescopically extended state. When landing or at rest on the ground, the weight of the aircraft on the landing gear compresses the air spring, forcing the strut to a relatively shortened state which may be a number of inches shorter than the extended state. With the aircraft airborne and the landing gears down, the unloaded gears and associated shock struts assume their fully extended state. Thus extended, the gears are rotated into the retracted position to reside within the wheel wells.
Although aircraft have heretofore been designed to accommodate the full, extended strut length when the landing gears are retracted, such a configuration does not always permit the most advantageous placement of the supporting structure for the gears. For example, landing gears are usually supported by mounts on the underside of the wings, and are rotatively retracted in a direction inboard, toward wheel wells disposed in the lower surface of the fuselage. As the length of the landing gears is increased, for example to achieve greater ground clearance during landing, it may be necessary to dispose the pivotal supports for the gears at increasingly greater outboard positions on the wings, where the wing structure is not as strong, in order to fit the strut and attached wheel assemblies within the wheel wells.